The expression and significance of E-selectin in lung tissue and serum of neonatal rats with acute lung injury / 中国新生儿科杂志

ABSTRACT

Objective To investigate the role and significance of E selectin in the pathogenesis of neonatal acute lung injury (ALI).Method Ninety neonatal Sprague Dawley (SD) rats (6 or 7 days after birth) were randomly assigned to the control group (n =10) and ALI group (n =80).The rats in the ALI group received intraperitoneal injection of lipopolysaccharide (LPS) at dose of 4 mg/kg and they were divided into eight subgroups with 10 rats in each group according to different sacrifice time (0.5 h,1 h,2 h,3 h,4 h,8 h,12 h and 24 h after injection).Rats in the control group were injected intraperitoneally the same volume of normal saline and they were sacrificed at 4 hours after injection.Expression of the E-selectin in lung tissue was detected dynamically by immunohistochemistry and the serum soluble endothelial selectin (sE-selection) was detected by enzyme-linked immunosorbent assay (ELISA).The pathological changes of the lung tissue and the wet/dry lung weight ratio (W/D ratio) were recorded.Result The strong expression of a large number of E-selectin was detected in the vascular endothelial cells of the lung tissue in the ALI group,while only moderate expression of E-selection was observed in the control group.The W/D ratio in the ALI group gradually increased from 0.5 h after intraperitoneal injection of LPS,reached the peak at 8 h,and then began to decline.The ratio was significantly higher in the ALI group than that of the control group from 4 to 12 h after injection (P ＜ 0.05).The mean optical density of E-selectin in lung tissue of ALI group was also higher than that of the control group and the average optical density of ALI group at 2 h,3 h,4 h and 8 h was significantly higher [2 h(0.36 ±0.09),3 h(0.38 ±0.01),4 h(0.44 ± 0.06),8 h(0.30 ± 0.09),control group(0.24 ± 0.01),P ＜ 0.05].The level of serum sE-selectin gradually increased after intraperitoneal injection of LPS,reached the peak at 2 h,and then decreased gradually.The level of sE selection was significantly higher than that of the control group at the point of 2 h,3 h,4 h and 8 h (P ＜ 0.05).The level of serum sE-selectin increased along with the expression of E-selectin in lung tissues,and they were positively correlated (r =0.730,P ＜ 0.01).Conclusion The increased expression of E-selectin and the elevation of serum sE-selectin level may reflect the injury of pulmonary vascular endothelial cells induced by systemic inflammatory response.